Hippocampus

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The hippocampus is a major component of the brains of humans and other mammals. It belongs to the limbic system and plays important roles in long-term memory and spatial navigation. Like the cerebral cortex, with which it is closely associated, it is a paired structure, with mirror-image halves in the left and right sides of the brain. In humans and other primates, the hippocampus is located inside the medial temporal lobe, beneath the cortical surface. Its curved shape reminded early anatomists of the horns of a ram (Cornu Ammonis), or a seahorse. The name, in fact, was taken by the sixteenth century anatomist Julius Caesar Aranzi from the Greek word for seahorse (Greek: ιππος, hippos = horse, καμπος, kampos = sea monster).

In Alzheimer's disease the hippocampus is one of the first regions of the brain to suffer damage; memory problems and disorientation appear among the first symptoms. Damage to the hippocampus can also result from oxygen starvation (hypoxia), encephalitis, or medial temporal lobe epilepsy. People with extensive hippocampal damage may experience amnesia—the inability to form or retain new memories.

In rodents, the hippocampus has been studied extensively as part of the brain system responsible for spatial memory and navigation. Many neurons in the rat and mouse hippocampus respond as place cells: that is, they fire bursts of action potentials when the animal passes through a specific part of its environment. Hippocampal place cells interact extensively with head direction cells, whose activity acts as an inertial compass, and with grid cells in the neighboring entorhinal cortex.

Because of its densely packed layers of neurons, the hippocampus has frequently been used as a model system for studying neurophysiology. The form of neural plasticity known as long-term potentiation (LTP) was first discovered to occur in the hippocampus and has often been studied in this structure. LTP is widely believed to be one of the main neural mechanisms by which memory is stored in the brain.

For more information about Hippocampus, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with hippocampus

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Modern human brain

Meditation increases brain gray matter

Medicine & Health / Neuroscience

created May 12, 2009 | popularity 4.5 / 5 (34) | comments 13

Push-ups, crunches, gyms, personal trainers -- people have many strategies for building bigger muscles and stronger bones. But what can one do to build a bigger brain? Meditate.


Why antidepressants don't work for so many

Medicine & Health / Psychology & Psychiatry

created Oct 23, 2009 | popularity 5 / 5 (24) | comments 4

More than half the people who take antidepressants for depression never get relief. Why? Because the cause of depression has been oversimplified and drugs designed to treat it aim at the wrong target, according to new research ...


Alzheimer's researchers find high protein diet shrinks brain

Medicine & Health / Neuroscience

created Oct 20, 2009 | popularity 4.7 / 5 (15) | comments 4

One of the many reasons to pick a low-calorie, low-fat diet rich in vegetables, fruits, and fish is that a host of epidemiological studies have suggested that such a diet may delay the onset or slow the progression of Alzheimer's ...


Smart rat 'Hobbie-J' produced by over-expressing a gene that helps brain cells communicate

Smart rat 'Hobbie-J' produced by over-expressing a gene that helps brain cells communicate

Biology / Biotechnology

created Oct 19, 2009 | popularity 4.9 / 5 (14) | comments 5

Over-expressing a gene that lets brain cells communicate just a fraction of a second longer makes a smarter rat, report researchers from the Medical College of Georgia and East China Normal University.


CIA's 'Enhanced Interrogation' Techniques Were Counterproductive

Medicine & Health / Neuroscience

created Sep 29, 2009 | popularity 3.9 / 5 (14) | comments 30

(PhysOrg.com) -- The author of a new report suggests the belief that harsh interrogation and torture techniques are effective is a form of folk neuroscience that is not supported by scientific evidence, and does not fit with ...


Researchers said they had pinpointed the biochemical pathway by which cannabis causes memory loss in mice

Pot shot: Scientists find cannabis trigger for forgetfulness

Medicine & Health / Neuroscience

created Aug 02, 2009 | popularity 4.9 / 5 (9) | comments 5

Researchers on Sunday said they had pinpointed the biochemical pathway by which cannabis causes memory loss in mice.


brain

Sleep helps build long-term memories

Medicine & Health / Neuroscience

created Jun 24, 2009 | popularity 4.8 / 5 (9) | comments 1

(PhysOrg.com) -- Experts have long suspected that part of the process of turning fleeting short-term memories into lasting long-term memories occurs during sleep. Now, researchers at the RIKEN-MIT Center for ...


Acute stress leaves epigenetic marks on the hippocampus

Medicine & Health / Psychology & Psychiatry

created Nov 24, 2009 | popularity 4.7 / 5 (9) | comments 0

(PhysOrg.com) -- Scientists are learning that the dynamic regulation of genes -- as much as the genes themselves -- shapes the fate of organisms. Now the discovery of a new epigenetic mechanism regulating genes in the brain ...


Neurobiologist proposes 'The end of sex as we once knew it'

Medicine & Health / Research

created Feb 02, 2009 | popularity 4.1 / 5 (10) | comments 4

(PhysOrg.com) -- Women are not from Venus any more than men are from Mars. But even though both sexes are perfectly terrestrial beings, they are not lacking in other differences. And not only in their reproductive organs ...


Now where did I leave my car -- and how do I get back there? How the brain translates memory into action

Medicine & Health / Neuroscience

created Apr 16, 2009 | popularity 4.6 / 5 (8) | comments 1

(PhysOrg.com) -- When we emerge from a supermarket laden down with bags and faced with a sea of vehicles, how do we remember where we've parked our car and translate the memory into the correct action to get back there? Scientists ...


neuron

To make memories, new neurons must erase older ones

Biology / Cell & Microbiology

created Nov 12, 2009 | popularity 4.4 / 5 (8) | comments 0

Short-term memory may depend in a surprising way on the ability of newly formed neurons to erase older connections. That's the conclusion of a report in the November 13th issue of the journal Cell that provid ...


Theory about long and short-term memory questioned

Medicine & Health / Neuroscience

created Nov 09, 2009 | popularity 4.7 / 5 (6) | comments 0

The long-held theory that our brains use different mechanisms for forming long-term and short-term memories has been challenged by new research from UCL, published today in PNAS.


rat

Rats' mental 'instant replay' drives next moves

Medicine & Health / Neuroscience

created Aug 26, 2009 | popularity 4 / 5 (6) | comments 0

(PhysOrg.com) -- Researchers at MIT’s Picower Institute for Learning and Memory have found that rats use a mental instant replay of their actions to help them decide what to do next, shedding new light on how ...


Oprah Winfrey

Oprah, Luke Skywalker and Maradona -- new study investigates how our brains respond to them

Medicine & Health / Neuroscience

created Jul 23, 2009 | popularity 4.6 / 5 (5) | comments 0

Pictures paint concepts of a thousand words- now, for the first time, scientists studying the brain have worked out how words paint concepts in our minds.


Birds in captivity lose hippocampal mass

Birds in captivity lose hippocampal mass

Biology / Plants & Animals

created Oct 12, 2009 | popularity 4.6 / 5 (5) | comments 2

(PhysOrg.com) -- Being in captivity for just a few weeks can reduce the volume of the hippocampus by as much as 23 percent, according to a new Cornell study.